Wood preservative



' R. H. HANDY woon PRESERVATIVE June 21,1927. '1,e33,09'5

Filed Feb. 5, 1925 fnaentor filial/16 Patented June 21, 1927.

PATENT OFFICE.

rum HOWARD HANDY, OF BERKELEY,

WOOD PBESEB VA'IIVE.

Application fled lama-1'8, 1985. Serial No. 6,650.

This invention relates to an improved wood preservative in the form of an emulsion particularly adapted to erform wood preserving functions as herea r described. 6 Due to their contact with the ground and the absorbing of moisture therefrom and the contracting of fun diseases, such wood bodies as railroad ties, telephone poles, etc., quickl become affected and decay. To pre- 10 vent t is action and preserve the wood, these bodies are now very commonly treated with a wood preservative. There are many of such preservatives now in use, most of which have an oil base. It is the primary ob ect of my invention to provide an improved wood preservative in the form of a waterin-oil emulsion containing wood preserving antiseptics.

A. wood preservative, to be most effective,

should have the following characteristics:

(1 Should be antiseptic.

(2 Should exclude airand moisture.

(3 Should be capable of giving up its antiseptic reservative in sufficient quanti- 95 ties to kill iostile fun and (4) Should be capa le of preventing the leaching out and deterioration of this antiseptic as long as possible. a

It is a further ob'ect of my invention to rovide an improve wood preservative emodying these characteristics.

With the above and other objects in view, 1

, my invention consists of the improved product and process defined herein and illustrated in the accompanying drawing. V It should be understood, however, that the invention is not to be limited to the s ific details defined herein, the scope oft e invention being defined in the appended claims.

In the fi ures of the drawing: Fig; 1 i ustrates a portion of my improved emulsion having as one'of its components a fuel oil of 28 A. P. I. or 28 gravity and,

Fi 2 is a like view illustrating the emul sion aving as one of its components a fuel oil of 17 A. P. I. or 17 gravity, both such views being illustrated as magnified 100 di- I ameters.

Certain chemical salts such for example, as zinc chloride, copper sulphate, mercuric chloride, sodium fluoride, etc. are highly antiseptlc to wood destroying fungi.

Likewise,the*tar acids, cresylic acid, carbolic acid, beta naphthol, creosote, etc.,

septics, as illustrated in the accompanying drawing. This emulsion is to be of the water-in-oil type wherein the water is the dispersed phase and the oil is the continuous phase. The water thereof will always be an antiseptic salt solution and the oil ma or may not contain an antiseptic as desire The water will always have some antiseptic' in solution though this may be a weak solution if desired. The oil may have no antiseptlc or any amount desired. .The emulsion may, therefore, comprise a water solution strongly antiseptic and little or no antiseptic in the oil, or the water may be a weak antiseptic solution and the oil corres ondingly strong with an antiseptic. Brie y, therefore, it is only necessary that the emulsion should be antlseptic and this antiseptic can be placed Wherever the same seems cheapest and most desirable. 1

It will be understood that my invention contemplates an emulsion of the above type and the manufacture thereof by any of the various possible methods. One of the preferred methods which I have devised for producing an emulsion of this type is by the use of zinc hydroxide as the emulsifyin agent. This zinc hydroxide is in this 'metho obtained by the chemical reaction between zinc chlori e and ammonium hydroxide, the

ammonium hydroxide being added to a v water solution of zinc chloride andthe chemical reaction being as follows:

ZnCl +2NH,OH=Zn (OH) ,'|-2NH,C1

ing z nc chloride solution which as above shown contains zinc hydroxide. The emulsion'is then made by adding the oil, with or without any miscible antiseptic constituabout 150 per cent. Beyond this point the ents, as desired, and shaking or beating the same into an emulsion. This emulsion will remain exceedingl stable.

I have found t at in an emulsion. made I with zinc hydroxide in the above manner,

the amount of water in proportion to the amount of oil may be varied, from a minimum of about 2 per-cent to a maximum of emulsion becomes somewhat unstable. emulsion may, therefore, be made very thin,

which is particularly desirable as a thin solution enters the wood much more readily in the treatin o eration.

The em i ying agent (zinc hydroxide in the above method) forms the oil and water into a water-in-oil emulsion as illustrated in the'accompanying'drawing. The oil 1 is the continuous phase and the water solution "2, formed into globules entirely surrounded sion. As a rule, the lightoils make larger lobules of water solution such as shown m Fig. 1, this being with an oil of 28 gravity while the heavier oils make finely dispersed particles of water solution as shown in Fig.

2, this beingwith an oil of 17 gravity. The heavier oil emulsion is believed to be considerably more desirable for various reasons, particularly since the same is more water proof and makes smaller water solution globules which are held more stable in the .oil. In both Figs. 1 and 2, the emulsion is illustrated as magnified 100 diameters.

t by weight:

An emulsion of this type particularly adapted for treating railroad ties may, for example, contain the following ingredients Per cent.

O 37.1 Cresylic a 1. 83 Water 57.75 Zinc chloride 2.89 Ammonium hydroxide;

This emulsion is made up of a 5 per cent solution of zinc chloride emulsified with a mineral oil having mixed therewith 5 per 60. cent of cresylic acid, the emulsification to take place by the addition of ammonium hydroxide to form the emulsifying agent of zinc hydroxide. The rcentage of cresylic acid and zinc hydrox de may be altered to suit other conditions, but the percentage above given is very suitable for railroad ties, which is one of the principal uses of the emulsion.

In the wood preservatives'now in use the water soluble antiseptics readily leach out of the wood, the preserving effect on the I wood thereby being lost. In my emulsion, these antiseptics in the water solution are entirely coated with a film of oil which retards such leaching action and retains the antiseptics in the wood for a longer period of time. Also, as stated above, the oil phase may always be made antiseptic if desired so that minute spores may not be able to make their way t rough the oil or the continuous phase of the emulsion.

Furthermore, in manufacturing my emulsion, advantage may be taken of the cost of the preservatives, either of oil miscible or water soluble, so as to make up preservative at the least possible cost according to the market pricesof the components. c

Having thus described my invention, What I claim and desire to secure by Letters Patent is 1. A wood preservative consisting of a water-in-oil emulsion wherein a water soluble antiseptic is contained within the water, and cresylic acid contained within the oil to act .as an antiseptic to wood destroying fungi.

2. The process of forming a water-in-oil wood preserving emulsion which consists of adding oil and ammonium hydroxide to a water solution of zinc chloride to form an emulsion, zince hydroxide formed by the reaction'of the zinc chloride and the ammonium hydroxide acting as an emulsifying agent therein to form a water-in-oil emulsion.

3. The process of forming a water-in-oil wood reserving emulsion which consists of provi ing a zinc chloride water solution and adding oil, cresylic acid, and ammonium hydroxide thereto to form an emulsion, zinc hydroxide formed by the reaction of the zinc chloride and ammonium hydroxide acting as an emulsifying agenttherein to form a water-in-oil emulsion. I

RALPH HOWARD 

